The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 26, 1988
Filed:
Nov. 26, 1986
Luigi Cazzaniga, Milan, IT;
Sparco, Inc., Cranston, RI (US);
Abstract
A power driven valve actuator includes a thermostatic device which is movably supported in a housing to accommodate overtravel of a thrust member against the stem of the valve resulting from excess expansion of a thermostatic element enclosed in the thermostatic device and heated by a heating device. Movement of the thermostatic device trips a dust-tight switch to interrupt power to the heating device, and a spring engaging the thermostatic device returns the thermostatic device to a starting position, so that whenever heat is called for by the thermostat, the thermostatic device cycles in a reciprocating motion within the housing after the valve has been fully opened. The heating device comprises an electric resistance heating element placed in contact with a thermal enclosure of the thermostatic element and covered by an insulating material.